// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'

Shader "Tut/Lighting/Blur/BlurEnergy_2B_JustBlur" {
	Properties {
		_MainTex ("Base (RGB)", 2D) = "white" {}
	}
	SubShader {
		 pass {
			  ZTest Always Cull Off ZWrite Off	  Fog { Mode off }      
			  CGPROGRAM
			  #pragma fragmentoption ARB_precision_hint_fastest
			  #pragma vertex vert
			  #pragma fragment frag
			  #pragma debug
			  #include "UnityCG.cginc"
			struct v2f {
				float4 pos : POSITION;
				half2 uv : TEXCOORD0;
				half2 taps[4] : TEXCOORD1; 
			};
			sampler2D _MainTex;
			half4 _MainTex_TexelSize;
			half4 _BlurOffsets;
			v2f vert( appdata_img v ) {
				v2f o; 
				o.pos = UnityObjectToClipPos(v.vertex);
				o.uv = v.texcoord - _BlurOffsets.xy * _MainTex_TexelSize.xy; // hack, see BlurEffect.cs for the reason for this. let's make a new blur effect soon
				o.taps[0] = o.uv + _MainTex_TexelSize * _BlurOffsets.xy;
				o.taps[1] = o.uv - _MainTex_TexelSize * _BlurOffsets.xy;
				o.taps[2] = o.uv + _MainTex_TexelSize * _BlurOffsets.xy * half2(1,-1);
				o.taps[3] = o.uv - _MainTex_TexelSize * _BlurOffsets.xy * half2(1,-1);
				return o;
			}
			half4 frag(v2f i) : COLOR {
				half4 color = tex2D(_MainTex, i.taps[0]);
				color += tex2D(_MainTex, i.taps[1]);
				color += tex2D(_MainTex, i.taps[2]);
				color += tex2D(_MainTex, i.taps[3]); 
				return color * 0.25;
			}
			  ENDCG
			  }//pass
		  }//sub
	FallBack "Diffuse"
}
